Latch unit



Nov. 27, 1962 E. E. DU FOUR 3,065,985

LATCH UNIT Filed May 25, 1961 INVENTOR. ERNEST E. DUFOUR United States Patent Office 3,065,985 LATCH UNIT Ernest E. Du Four, Elkhart, Ind., assignor t Ekco Products Company, Chicago, 11]., a corporation of Delaware Filed May 25, 1961, Ser. No. 112,642 2 Claims. (Cl. 292-103) This invention relates to a latch unit and more particularly a latch unit for use in sliding door installations.

An important object of this invention is to provide a latch unit having a pivoted latching member movable between an operative extended position and an inoperative retracted position and spring means with which said latching member has engagement for resiliently holding the latching member in its operative and inoperative positions.

A further object is to provide a latch unit incorporating a design and assembly of parts which make the unit economical to manufacture, as well as durable and reliable in operation.

With the foregoing objects in view, and such other objects and advantages as will become apparent to those skilled in the art to which this invention relates as this specification proceeds, my invention consists essentially in the arrangement and construction of parts all as hereinafter more particularly described, reference being had to the accompanying drawings in which FIG. 1 is a fragmentary side elevational view of a door and doorway installation illustrating a latch unit applied thereto in accordance with the present invention.

FIG. 2 is an enlarged fragmentary horizontal section taken along line 2-2 of FIG. 1, with parts in elevation.

FIG. 3 is a fragmentary vertical section taken along line 3-3 of FIG. 2.

FIG. 4 is a similar view showing the latching member in idle position.

FIG. 5 is an enlarged fragmentary vertical section taken along line 55 of FIG. 2 with parts removed.

FIG. 6 is an enlarged perspective view of an indexing member employed in connection with a latching unit according to this invention.

FIG. 7 is an enlarged fragmentary vertical section taken along line 77 of FIG. 5.

The drawings illustrate a latching unit as applied to an installation wherein a door 10 is slidable between open and closed positions relative to a doorway defined along one side thereof by a door frame 11. The unit is however equally applicable to an installation wherein a second door is substituted for the frame 11.

As shown in FIG. 3, the edge 13 of the door 10 facing the frame 11 is intersected by a recess 12. Reference numeral 14 designates a front wall member positioned across the recess 12 in a plane substantially flush with edge surfaces 13 of the door 10 above and below the re cess 12. The front wall member 14 is provided with an opening 15 occupying a position centrally of opposite upright edges of the member 14. Member 14 is secured in fixed relation to the door 10 by means of mounting plates 16 and 17 extending rearwardly from opposite upright edges of the front member 14 in straddling relation to opposite face portions of the door 10 defining the upper, lower and rear limits of the recess 12. The plates 16 and 17 are respectively fastened to the surfaces of the door 10* overlapped thereby by screws 18 entering the door 10. The front wall member 14 and plates 16 and 17 thus cooperate with the surfaces of the door 10 defining the recess 12 to provide a casing having a front- Ward facing opening 15. A bracket secured to the front member 14 along opposite upright edges of the latter includes a pair of arms 19 which extend rearwardly from the front member 14 in spaced apart parallel relation ap- 3,065,985 Patented Nov. 27, 1952 proximately aligned with opposite upright edges of the opening 15. Each of said arms 19 is secured to the mounting plate 16 or 17 opposite thereto by means of screws 20.

Each arm 19 has a flange 19a. forming a rearward inwardly offset extension of the arm. The flanges 19a are; brought together in face to face relation and riveted as at. 21 to secure a tight connection of said flanges above and-1 below a central embossed area creating opposed walls 22, of a passageway forming a rearward continuation of the: space between said arms 19. A shaft 23 having bearing: support in horizontally aligned openings in said walls 22 provides an axis about which a latching member 24 mounted on said shaft has upward and downward rocking movement.

As shown in FIG. 7; the shaft 23 is a relatively enlarged cross sectional contour along the portion 25 thereof between the walls 22 so as to present axially facing shoulders with which the inner surfaces of the wings 22 have engagement to trap the shaft 23 against withdrawal from its bearing supports in the walls 22. It will also be noted that the portion 25 and the opening in the latching memher through which the shaft portion 25 projects are of matching non-circular cross section to establish a driving connection between the shaft 23 and the latching member 24. The shaft 23 has an axial passageway therethrough so as to provide a socket 26 of non-circular contour opening toward the mounting plate 17 and a socket 27 of similar contour opening toward the mounting plate 16. Operation of the latching mechanism may be accomplished from the side of the door containing mounting plate 16 or from the side of the door containing mounting plate 17, by means of an actuating key 28 having a shank portion 29. As shown in the drawings, an open-- ing is provided in the mounting plate 17 in axial alignment with the shaft 24 through which the shank portion. 29 projects for interfitting engagement with the socket 25 facing plate 17. A similar opening in the mounting plate; 16 accommodates the shank portion 31 of a second key 30 for interfitting engagement with the socket 27 facing; mounting plate 16. A washer 32 forced on shank 29 and a similar washer 33 on shank 31 have engagement with the inner surfaces of mounting plates opposite thereto to secure said actuating keys 28 and 36 against withdrawal from the shaft 23.

The latching member includes a hooked end portion 34 which when occupying an advanced position in horizontally protruding relation to the front wall 14 of the latch casing is in a position to engage the edge 35 of a strike plate 36 on the frame 11 facing the front wall 14 of the latch casing to establish a locking of the door 10 in closed position relative to the frame 11. Upon movement of the latching member 24 to disengage the hook 34 from said strike plate 36 and thereby release the door 10 for movement away from the frame 11, the latching member is tilted upwardly, as shown in FIG. 4 to assume a position wherein the hook 34 is fully retracted within the confines of front wall 14 of the latch casing.

It will be noted that shoulders 37 defined along rearwardly converging lines at the juncture between the walls 22 and the areas of the flange 19a above and below said walls 22 provide stops with which the latching member 24 has engagement to establish the range of rocking movement of the latter between advanced and retracted positions.-

In order to resist return of the latch member from a retracted upwardly rocked position to said advanced position after being moved to said retracted position, the latch member is provided with a radially extending ear 38 in rearwardly protruding relation to the rear limits of the walls 22 for cooperation with an indexing member.

As shown in FIG. 6, the indexing member is in the form of a leaf spring having forwardly bent arms 39 and 40 at opposite ends thereof and a forwar ly protecting hump 41 intermediate said ends. Mounting ears 42 formed integrally with the flanges 19a and extending in opposite directions along a vertical line at the rear edge of the walls 22 engage slots 43 provided in each of the arms 39 and 46 of the leaf spring to secure the latter rearwardly opposite the path of the ear 3% of the latching r ember. The car 33 accordingly acts to displace the hump 41 in a rearward direction incident to movement of the latching member between retracted and advanced positions of the latching member whereby the indexing member is operative to maintain the ear 3% either above or below the hump 41 to releasably resist return of the latch member from retracted position to advanced position or from advanced position to retracted position.

The hump 41 is therefore effective to maintain the latching member in selected advanced or retracted position and thereby avoid inopportune locking or unlocking conditions due to accidental vibrations. However the hump 41 is also effective to urge the hook 34 downwardly into engaged relation to the edge 35 of the strike plate 36 from an upwardly tilted position adequate to clear the edge 35 incident to entry of the hook 34 to said area behind the strike plate from a position approaching said strike plate while the latching member is in advanced position during such approach, since the travel of the ear 3% during such slight upward movement of the latching member is short of the distance required to pass to the other side of the hump 41 and thereby places the spring under stress to return the hook 34 to its lowered position.

To provide a pull element for use in moving the door .10 from an open position to a closed position relative to the frame 11, the drawings illustrate a latch unit having a pull plate 4-4 which is adapted to swing about a pivot pin 45 between an upwardly swung position in horizontally extending relation to the upper limits of the opening 15 in the front wall 14 of the latch casing as shown in FIG. 4 and a downwardly swung position in closing relation to said opening 15 in the front wall 14, as shown in FIG. 3. The plate 44 has an elongated opening 46 in which the latching member has clearance for movement between advanced and retracted position.

What is claimed is:

1. in a latch unit, a hollow casing having a front wall t. and an opening in said front wall having spaced apart parallel upright edge portions, a bracket comprising a pair of arms secured in fixed relation to said casing and extending rearwardly from said front wall along spaced parallel planes approximately aligned with opposite upright edge portions of said opening in said front wall, means forming a rearwardly open passageway as a rearward continuation of the space between said arms, said means including flanges forming rearward extensions of said arms, said flanges being separated along a central area and joined along inwardly offset areas above and below said central area, a pair of cars forming integral extensions of said flanges above and below the rear limits of the passageway defined by said flanges, a shaft having bearing support in said central area of said flanges, a manually operable latch member supported on said shaft as a pivotal axis for movement of said latch member between an advanced position in outwardly protruding relation to said case through said opening in said front wall and a retracted position within the confines of said casing, said latch member having a radially facing indexing cam surface protruding rearwardly from the rear limits of said passageway defined by said central area of said flanges, and spring means operative to selectively retain said latch member in either of said positions, said spring means including a leaf spring having opposite end portions thereof releasably fastened to said ears and a hump intermediate opposite ends of said spring adapted to be displaced in a direction away from the pivot axis of the latch member by engagement with said indexing cam surface of the latch member incident to movement of the latter from one to the other of its said positions.

2. In a latch unit according to claim 1, wherein rearwardly converging shoulders are defined by the junction of said central area and said inwardly offset areas of the flanges above and below said central area, and said shoulders define stops with which the latching member has engagement to establish the range of movement of said member between advanced and retracted positions.

Sigler Dec. 10, 1901. Worthen Dec. 4, 1928 

